JP2008107721A - Board connecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a board connecting device that does not cause attraction error upon attracting a flexible board mounted on a table, with a bonding head (attraction head) even when a connection width of a FPC (flexible printed circuit) is decreased. <P>SOLUTION: The board connecting device is constituted so that a flexible board 8 mounted on an upper face of a table is attracted with an attraction head 19 and the lower face at an end of the flexible board 8 attracted by the attraction head 19 is pressure-bonded to the upper face at an end of a panel substrate 7, wherein the attraction head 19 is provided with an attraction part attracting the upper face of a part excluding the end of the flexible board 8 and a pressure-bonding part 26 pressure-bonding the lower face of the end to the panel substrate 7 by abutting on the upper face of the end, and the pressure-bonding part 26 is protruded toward the flexible board from the attraction part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a board connecting device for connecting a flexible board to a panel board such as a liquid crystal panel.

  In manufacturing a liquid crystal display device, this type of substrate connection device is used for a circuit board or other member such as an FPC (Flexible Printed Circuit) connected to a glass substrate of a liquid crystal display panel via an ACF (Anisotropic Conductive Film). It is used to connect component materials such as other substrates and electronic components.

  Conventionally, a COF (Chip On Film) method and a COG (Chip On Glass) method are known as connection methods using this substrate connection device.

  FIG. 11 is a plan view of a conventional COF type liquid crystal display module. A plurality of source TCPs (Tape Carrier Package) 102 are connected to one side of the liquid crystal panel 101a, and the plurality of source TCPs 102 are further connected to one source PCB (Print Circuit Board) 103a.

  In addition, a plurality of gate TCPs 104 are connected to the other side of the liquid crystal panel 101a, and further connected to one gate PCB 105a.

  Each member is connected via an ACF (Anisotropic Conductive Film), and the liquid crystal panel 101a, the source TCP 102 and the source PCB 103a, and the liquid crystal panel 101a, the gate TCP 104, and the gate PCB 105a are electrically connected. It is connected.

  Each member is thermocompression bonded after being relatively aligned by the image recognition means, and is connected with high accuracy (see, for example, Patent Document 1).

  When connecting the liquid crystal panel and each TCP, the ACF may be pasted first on the liquid crystal panel side or the TCP side, but it must be pasted on the liquid crystal panel side where batch attachment is possible due to workability problems. Many. Similarly, when connecting a plurality of TCPs to each PCB, the ACF may be pasted first on the TCP side or on the PCB side, but it may be pasted on the PCB side where workability is good and batch pasting is possible. Many.

  The liquid crystal panel and source TCP, and the liquid crystal panel and gate TCP are relatively accurately aligned by image recognition means, relatively low temperature (50 ° C to 80 ° C), short time (0.5 seconds to 2 seconds), After temporarily connecting each TCP individually at a low pressure (0.5 MPa to 1 MPa), one side of the liquid crystal panel is put together to make multiple TCPs high temperature (150 ° C. to 200 ° C.), long time (10 seconds to 20 seconds), high pressure ( The main connection is performed at 2 MPa to 3 MPa.

  The bonding head (adsorption head) that performs the temporary connection has a vacuum suction hole in the crimping tool portion, and has an integrated structure that allows the temporary connection operation to be continuously performed while the TCP is vacuum-adsorbed and aligned (for example, , See Patent Document 2).

  The crimping tool part of the bonding head that temporarily connects the TCP to the liquid crystal panel has an important role of sucking and holding the TCP, and a suction hole large enough to stably hold the TCP is necessary. If a φ1 mm suction hole is provided in a row, the crimping tool width is about 2 mm. If the suction hole diameter is too small, it is difficult to stably hold the TCP, and it is difficult to narrow the crimping tool width to 1 mm or less.

  In recent years, the width of the TCP connection part of the liquid crystal panel has become narrower due to space saving, and the actual situation is that it is narrower than the crimping tool width. When making a connection, the TCP terminal may be disconnected (see, for example, Patent Document 3).

  By the way, in recent years, the COG (Chip On Glass) system has become the mainstream in the medium and small size liquid crystal display panels of 10 type or less instead of the COF system.

FIG. 12 is a plan view of a COG type liquid crystal display module.
In this COG method, a gate driver IC 109a and a source driver IC 109b are directly mounted on two sides of the liquid crystal panel 101b, and the liquid crystal panel 101b and the gate PCB 105b are collectively relayed via a gate FPC (Flexible Print Circuit) 108a. In addition, the liquid crystal panel 101b and the source PCB 103b are collectively relayed via the source FPC 108b.

  When connecting the PCB and the FPC, the ACF is first attached to the PCB side as in the COF method. The reason is that FPC is weak in strength and easily deforms. When connecting a liquid crystal panel to an FPC, I would like to make a connection by attaching the ACF to the strong liquid crystal panel first, but the driver LSI is mounted on the FPC connection part of the liquid crystal panel first. Yes. If the ACF is attached to the FPC connection portion of the liquid crystal panel, there is a risk of damaging the driving LSI. Therefore, the ACF of the liquid crystal panel and the FPC connection portion is often attached to the FPC side.

  One of the merits of the COG method is cost reduction. In the COF method, the chip is converted into a TCP by FPC bonding for the first time, and the bonding is performed for the second time on the panel through an outer shape extraction process with a mold. Significant cost reduction is possible due to the extra bonding and outline removal process and the reduction of intermediate materials.

In the COG method, accuracy merit is also important. In the COF method, a difference in elongation due to heat occurs due to a difference in material between TCP and panel. When considering the electrode pitch to be connected as 50 μm and the terminal width as 25 μm, it is at the limit when including component accuracy, mounting accuracy, and thermal elongation. In the COG method, an intermediate material is not used, and high-precision mounting can be performed without being affected by the elongation of the material due to heat.
Japanese Patent Laid-Open No. 11-186701 Japanese Patent Laid-Open No. 10-107088 JP 2004-63399 A

  As described above, in the COF method, the separated TCP is connected to the liquid crystal display panel. The bonding head (adsorption head) at that time has used a small bonding head in accordance with the TCP size.

  However, in the COG method, it is necessary to connect the liquid crystal panel and the PCB substrate with a single FPC, and a large bonding head is used to stably hold and hold a large FPC for accurate positioning. Development is needed.

  However, FPC is a thin film material that is weak in strength and easily deformed. Even when placed on the temporary table, the end of the FPC is warped or partly wavy.

  In the conventional bonding head in which the suction hole is simply machined in the crimping tool portion, it is difficult to stably receive the FPC from the temporary placement table, suction mistakes frequently occur, and the equipment operation rate decreases.

  Furthermore, if the bonding head receives the FPC in a deformed state, connection failure occurs due to connection to the liquid crystal panel substrate, and connection reliability is lowered.

  Also, as the FPC connection part on the panel side becomes narrower, it becomes necessary to narrow the crimping tool width of the bonding head, but it is a fact that the crimping tool width is narrowed while maintaining the FPC suction holding force. It is difficult.

  Accordingly, the present invention provides a substrate connecting apparatus that prevents a suction error from occurring when a flexible substrate placed on a table is sucked by a bonding head (suction head) even if the connection width of the FPC becomes narrow. The purpose is to do.

  In order to achieve the above object, the present invention has taken the following measures. That is, the present invention is characterized in that the flexible substrate placed on the upper surface of the table is adsorbed by the adsorption head, and the lower surface of the end of the flexible substrate adsorbed by the adsorption head is used as the upper surface of the end of the panel substrate. In the substrate connecting apparatus that is crimped to the suction head, the suction head includes a suction portion that sucks an upper surface of a portion that is not an end portion of the flexible substrate, and a lower surface of the end portion that is in contact with the upper surface of the end portion. There is provided a crimping portion for crimping to the panel substrate, and the crimping portion protrudes from the suction portion toward the flexible substrate.

  It is preferable that the suction part is provided with a suction hole or a suction pad for sucking the flexible substrate.

It is preferable that no suction hole is provided in the crimping portion.
It is preferable that the said crimping | compression-bonding part contacts the flexible substrate adsorbed by the said adsorption | suction part, and corrects a deformation | transformation of a flexible substrate.

  The crimping part is for thermocompression bonding of the flexible substrate to the panel substrate via the ACF, and the width of the crimping part is preferably substantially the same as the width of the ACF.

  The crimping part and the suction part are formed on flat surfaces parallel to each other, the step between them is 0.5 mm to 1.0 mm, and the width of the crimping part is 0.5 mm to 0.8 mm. preferable.

  According to the present invention, the flexible substrate placed on the upper surface of the table is sucked and held by the suction portion of the suction head at the upper surface of the portion that is not the end portion. Mistakes disappear.

  During the suction, the end of the flexible substrate is forcibly warped by the crimping portion protruding from the suction portion, so that the warp deformation and the wavy deformation of the end of the flexible substrate are corrected to a flat shape. Therefore, the crimping | compression-bonding mistake by a crimping | compression-bonding part is prevented.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an overall view of a substrate connecting apparatus according to the present invention. An outline of the apparatus will be given in the order that the process proceeds from the left to the right of the apparatus.

  The board connecting device includes a panel supply device 1 provided at the left end, an alignment temporary pressure bonding device 2 provided on the right side thereof, a flexible substrate supply device 3 provided in front thereof, and a right side of the temporary pressure bonding device 2. And the panel take-out device 5 provided on the right side thereof.

  The panel supply device 1 has a panel supply tray 6 in which a panel substrate 7 is accommodated. An example of the panel substrate 7 is a glass substrate before FPC connection of a liquid crystal panel of a liquid crystal display module. This panel supply apparatus 1 takes out the panel board | substrate 7 accommodated in the panel supply tray 6 one by one, and transfers it to the positioning temporary crimping | compression-bonding apparatus 2. FIG.

  The flexible substrate supply device 3 is installed on the front surface of the alignment temporary pressure bonding device 2 and supplies the flexible substrate 8 to the temporary pressure bonding device 2. An example of the flexible substrate 8 is an FPC.

  The alignment temporary press-bonding device 2 is an apparatus for positioning and temporarily connecting the FPC 8 supplied from the flexible substrate supply device 3 and the panel substrate 7 transferred from the panel supply device 1 with high accuracy by image processing means. is there.

  The main press-bonding device 4 is a main pressure-bonding of the panel substrate 7 and the FPC 8 temporarily connected by the temporary press-bonding device 2 by setting the temperature, load and time satisfying the ACF curing condition. In the present embodiment, the ACF is provided in a strip shape on the lower surface of the flexible substrate (FPC).

  The panel take-out device 5 has a take-out tray 9, and stores the panel substrate (after FPC connection) 7 crimped by the main crimping device 4 in the take-out tray 9.

  FIG. 2 is a perspective view of a panel substrate (before FPC connection) 7 housed in the panel supply tray 6. The panel substrate 7 is illustrated as having a gate driver IC 10 and a source driver IC 11 already connected thereto.

FIG. 3 is a schematic configuration diagram of the positioning temporary press-bonding device 2.
A table 12 for supplying the FPC 8 from the flexible substrate supply device 3 to the alignment temporary pressure bonding device 2 is provided. The table 12 is a slide type and is provided so as to be movable on the guide rail 13. The FPC 8 is placed on the upper surface of the table 12 from the flexible substrate supply device 3 and is conveyed to the inside of the alignment temporary press-bonding device 2.

  A bonding head portion 14 is provided above the table 12. The bonding head unit 14 is supported by the alignment drive unit 15. The alignment drive unit 15 enables the bonding head unit 14 to be operated in the X, Y, and Z directions and in the horizontal direction.

  A panel mounting table 16 is provided below the alignment drive unit 15. A backup block 17 is provided between the panel mounting table 16 and the table 12. Image processing cameras 18 are arranged on the left and right sides of the backup block 17.

  The bonding head portion 14 integrally has a suction head 19 at a lower portion thereof, and holds the FPC 8 on the table 12 by suction on the lower surface of the suction head 19.

  A panel substrate 7 supplied from the panel supply device 1 is mounted on the panel mounting table 16.

  As shown in FIG. 4, the upper surface of the table 12 is a flat surface. In the table 12, a suction pad 20 for sucking and holding the lower surface of the flexible substrate 8 is embedded in a suction hole. A pipe 21 connected to a decompression device (not shown) is connected to the table 12. A communication hole that communicates the pipe 21 and the suction pad 20 is provided in the table 12.

  Positioning pins 12a project from two positions on the left and right of the table upper surface. The positioning pin 12a is for preventing the position shift of the FPC 8. Therefore, the FPC 8 is provided with a positioning hole corresponding to the positioning pin 12a.

  FIG. 5 is a perspective view of the bonding head unit 14. The bonding head unit 14 includes a heater block 22 and the suction head 19.

  A heater 23 and a thermocouple 24 are incorporated in the heater block 22, and the suction head 19 can be maintained at a set temporary connection temperature condition by a temperature controller (not shown).

FIG. 6 is a perspective view of the lower surface side of the suction head 19.
The suction head 19 includes a suction portion 25 that sucks the upper surface of a portion that is not an end portion of the flexible substrate 8, and a crimping portion that abuts the upper surface of the end portion and presses the lower surface of the end portion against the panel substrate 7. 26. The crimping portion 26 protrudes toward the flexible substrate side from the suction portion 25.

  The pressure-bonding portion 26 and the suction portion 25 of the suction head 19 are formed on flat surfaces parallel to each other.

  The pressure-bonding portion 26 has a structure in which the width is narrow and the suction hole for sucking the FPC 8 is not processed.

  On the other hand, a suction pad 27 for sucking and holding the FPC 8 is embedded in the suction portion 25. The suction pad 27 is connected to the heat resistant tube 28 through the inside of the suction head 19. The heat-resistant tube 28 is further connected to a vacuum generator (not shown).

  A groove 25a is recessed along the longitudinal direction of the suction portion 25 adjacent to the crimping portion 26, and a suction pad 27 is provided in the groove 25a. Further, in the suction part 25 at a position away from the crimping part 26, a hole 25b is formed, and a suction pad 27 is provided in the hole 25b.

  FIG. 7 is a cross-sectional view showing a state immediately before the FPC 8 is sucked and held by the FPC temporary placement table 12 and the FPC 8 is sucked by the suction head 19.

  The ACF sticking position 29 of the FPC 8 held by suction on the FPC temporary placement table 12 is in a state of protruding from the FPC temporary placement table 12 and hanging down.

  In this state, the suction part 25 of the suction head 19 is depressurized, and at the same time, the suction of the suction pad 20 of the table 12 is released. Then, the flexible substrate 8 on the table 12 is sucked by the suction portion 25 of the suction head 19.

  FIG. 8 is an enlarged view of the suction state of the flexible substrate 8 by the suction head 19. Since the step a is formed between the suction portion 25 and the pressure-bonding portion 26 of the suction head 19, the end of the flexible substrate 8 is warped by the edge of the pressure-bonding portion 26. The deformation of the part is corrected. The width b of the crimping portion 26 is set to be a narrow width that is substantially the same as the width of the ACF 29.

  In this embodiment, the level difference a is 0.5 mm to 1.0 mm. The width b of the crimping part 26 is 0.5 mm to 0.8 mm.

  Note that, due to the buffer effect of the suction pad 27 attached to the suction portion 25 of the suction head 19, even the FPC 8 that protrudes from the temporary placement table 12 and hangs down can be stably sucked and received.

  As shown in FIG. 3, the flexible substrate 8 sucked by the suction head 19 of the bonding head portion 14 is a panel on the panel mounting table 16 on which a temporary press-bonding process, which is the next process, is performed by the alignment driving unit 15. It is transferred to the upper end of the substrate 7.

  The alignment drive unit 15 includes an alignment mark (not shown) printed on both ends of the FPC 8 sucked and held by the suction head 19 and an alignment mark provided on the panel substrate 7 on the panel mounting table 16. Reading is performed by the two image processing cameras 18 and 18 installed on the left and right, and the bonding head unit 14 is relatively positioned.

  FIG. 9 shows the positioned state, and shows a state where the FPC 8 is sucked and held by the suction head 19. Furthermore, only the height direction of the position where the panel substrate 7 and the FPC 8 are connected is different.

  The positional relationship that the ACF application position 29 receives by the pressure-bonding portion 26 of the suction head 19 when the FPC 8 is sucked by the suction portion 25 of the suction head 19 is shown.

  The pressure-bonding position (ACF application position) of the FPC 8 is supported by the pressure-bonding portion 26 of the suction head 19 and is maintained in a horizontal state, and the FPC 8 is connected to the panel substrate 7 when the suction head 19 is lowered.

  That is, the bonding head unit 14 is lowered to temporarily connect the FPC 8 to the panel substrate 7. At the time of temporary connection, a load is applied to the back side of the panel substrate 7 by the backup block 17 in order to prevent deformation and breakage of the panel substrate 7. This temporary pressure bonding is performed at a relatively low temperature (50 ° C. to 80 ° C.), a short time (0.5 seconds to 2 seconds), and a low pressure (0.5 MPa to 1 MPa).

  When the temporary crimping is completed, the panel substrate 7 to which the FPC 8 is temporarily connected is transferred to the final crimping apparatus 4 shown in FIG. 1, and the final crimping is performed at a high temperature (150 ° C. to 200 ° C.) for a long time (10 seconds to 20 seconds). It is performed at high pressure (2 MPa to 3 MPa). When the main press bonding is completed, the panel substrate 7 is transferred to the panel take-out device 5.

  As is clear from the above description, the crimping portion 26 is in contact with the flexible substrate 8 sucked by the suction portion 25 to correct the deformation of the flexible substrate. The crimping portion 26 is for thermocompression bonding the flexible substrate 8 to the panel substrate 7 via the ACF 29.

  FIG. 10 is a perspective view of the panel substrate 7 accommodated in the take-out tray 9 of the panel take-out device 5. A gate FPC 8 a and a source FPC 8 b are connected to the panel substrate 7.

  As is clear from the above, according to the embodiment of the present invention, even if the crimping width of the connection portion between the panel substrate 7 and the FPC 8 is narrow, it is not affected by the suction holding force and ensures a sufficient crimping width. In addition, it is possible to perform stable thermocompression bonding and improve connection reliability.

  Further, even when the ACF sticking portion 29 of the FPC 8 is deformed on the temporary placement table 12, the suction head 19 can surely suck and receive, and the equipment operation rate is improved.

  Connection accuracy is achieved by supporting the FPC 8 with a flat crimping part 26 with no suction holes or the like, aligning it while preventing drooping of the end of the FPC 8 or part of the wavy deformation, and thermocompression bonding. Will improve.

  Further, in the conventional method in which suction holes are provided in the crimping portion and the FPC is sucked and held, three steps of alignment → temporary crimping → main crimping are required. This is because the temporary crimping tool used in the temporary crimping is difficult to crimp at the suction hole portion, so that it is necessary to perform the crimping by dividing the process.

  On the other hand, according to the embodiment of the present invention, there is no hole processing for FPC suction in the crimping portion 26, and the main crimping by the continuous operation can be performed following the alignment.

  As a result, the connection is completed in two steps from alignment to final crimping. This effect can be expected to greatly reduce tact time and downsize production equipment.

  In addition, the said embodiment disclosed this time is an illustration in all the points, Comprising: It is not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and includes all modifications within the scope and meaning equivalent to the terms of the claims.

  For example, the flexible substrate 8 is not limited to the FPC, and may be a PCB or other thin sheet-like connected substrate. Further, the suction portion 25 of the suction head 19 is not limited to the suction pad 27 but may be a suction hole. The board connecting apparatus of the present invention does not need to include all the apparatuses shown in FIG.

1 is an overall perspective view of a substrate connecting apparatus according to an embodiment of the present invention. It is a perspective view which shows the panel board | substrate used for embodiment of this invention. It is a perspective view which shows the structure inside the temporary crimping | compression-bonding apparatus which shows embodiment of this invention. It is a perspective view of the table of embodiment of this invention. It is a perspective view of the bonding head which shows embodiment of this invention. It is the perspective view seen from the back side of the adsorption head concerning an embodiment of the invention. It is sectional drawing which shows the relationship between the table which concerns on embodiment of this invention, and a suction head. It is a principal part expanded sectional view which shows the suction state of the flexible substrate by the suction head which concerns on embodiment of this invention. It is explanatory drawing of positioning of the panel substrate and flexible substrate which concern on embodiment of this invention. It is a perspective view which shows the panel of the state which connected the flexible substrate. It is the schematic which shows the external appearance of a COF system liquid crystal display module. It is the schematic which shows the external appearance of a COG system liquid crystal display module.

Explanation of symbols

  7 Panel substrate, 8 Flexible substrate, 12 Table, 19 Suction head, 25 Suction part, 25c Suction hole, 26 Crimp part, 27 Suction pad.

Claims (6)

In the substrate connection apparatus that sucks the flexible substrate placed on the upper surface of the table with the suction head and presses the lower surface of the end of the flexible substrate sucked by the suction head to the upper surface of the end of the panel substrate.
The suction head includes a suction portion that sucks an upper surface of a portion that is not an end portion of the flexible substrate, and a crimping portion that contacts the upper surface of the end portion and presses the lower surface of the end portion against the panel substrate. ,
The board connecting device, wherein the crimping part protrudes toward the flexible board rather than the suction part.   The board connection device according to claim 1, wherein the suction part is provided with a suction hole or a suction pad for sucking the flexible substrate.   The board connection device according to claim 1, wherein the crimping portion is not provided with a suction hole.   The board connection device according to claim 1, wherein the pressure-bonding part is in contact with the flexible board sucked by the suction part to correct deformation of the flexible board.   The said crimping | compression-bonding part thermocompression-bonds a flexible substrate to a panel board | substrate via ACF, The width | variety of the said crimping | compression-bonding part is made substantially the same as the width | variety of the said ACF, The 1-3 characterized by the above-mentioned. The board | substrate connection apparatus as described in any one of these.   The crimping part and the suction part are formed on flat surfaces parallel to each other, the step between the two is 0.5 mm to 1.0 mm, and the width of the crimping part is 0.5 mm to 0.8 mm. The board | substrate connection apparatus as described in any one of Claims 1-3 characterized by the above-mentioned.

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